/*
 * Copyright 2002-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.test.web.reactive.server;

import java.time.Duration;
import java.util.List;
import java.util.function.Consumer;

import org.springframework.http.HttpHeaders;
import org.springframework.http.client.reactive.ClientHttpConnector;
import org.springframework.http.client.reactive.ReactorClientHttpConnector;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.MultiValueMap;
import org.springframework.web.reactive.function.client.ExchangeFilterFunction;
import org.springframework.web.reactive.function.client.ExchangeStrategies;
import org.springframework.web.reactive.function.client.WebClient;
import org.springframework.web.server.adapter.WebHttpHandlerBuilder;
import org.springframework.web.util.UriBuilderFactory;

/**
 * Default implementation of {@link WebTestClient.Builder}.
 *
 * @author Rossen Stoyanchev
 * @since 5.0
 */
class DefaultWebTestClientBuilder implements WebTestClient.Builder {

    private final WebClient.Builder webClientBuilder;

    @Nullable
    private final WebHttpHandlerBuilder httpHandlerBuilder;

    @Nullable
    private final ClientHttpConnector connector;

    @Nullable
    private Duration responseTimeout;


    /**
     * Connect to server via Reactor Netty.
     */
    DefaultWebTestClientBuilder() {
        this(new ReactorClientHttpConnector());
    }

    /**
     * Connect to server through the given connector.
     */
    DefaultWebTestClientBuilder(ClientHttpConnector connector) {
        this(null, null, connector, null);
    }

    /**
     * Connect to given mock server with mock request and response.
     */
    DefaultWebTestClientBuilder(WebHttpHandlerBuilder httpHandlerBuilder) {
        this(null, httpHandlerBuilder, null, null);
    }

    /**
     * Copy constructor.
     */
    DefaultWebTestClientBuilder(DefaultWebTestClientBuilder other) {
        this(other.webClientBuilder.clone(), other.httpHandlerBuilder, other.connector,
                other.responseTimeout);
    }

    private DefaultWebTestClientBuilder(@Nullable WebClient.Builder webClientBuilder,
                                        @Nullable WebHttpHandlerBuilder httpHandlerBuilder, @Nullable ClientHttpConnector connector,
                                        @Nullable Duration responseTimeout) {

        Assert.isTrue(httpHandlerBuilder != null || connector != null,
                "Either WebHttpHandlerBuilder or ClientHttpConnector must be provided");

        this.webClientBuilder = (webClientBuilder != null ? webClientBuilder : WebClient.builder());
        this.httpHandlerBuilder = (httpHandlerBuilder != null ? httpHandlerBuilder.clone() : null);
        this.connector = connector;
        this.responseTimeout = responseTimeout;
    }


    @Override
    public WebTestClient.Builder baseUrl(String baseUrl) {
        this.webClientBuilder.baseUrl(baseUrl);
        return this;
    }

    @Override
    public WebTestClient.Builder uriBuilderFactory(UriBuilderFactory uriBuilderFactory) {
        this.webClientBuilder.uriBuilderFactory(uriBuilderFactory);
        return this;
    }

    @Override
    public WebTestClient.Builder defaultHeader(String headerName, String... headerValues) {
        this.webClientBuilder.defaultHeader(headerName, headerValues);
        return this;
    }

    @Override
    public WebTestClient.Builder defaultHeaders(Consumer<HttpHeaders> headersConsumer) {
        this.webClientBuilder.defaultHeaders(headersConsumer);
        return this;
    }

    @Override
    public WebTestClient.Builder defaultCookie(String cookieName, String... cookieValues) {
        this.webClientBuilder.defaultCookie(cookieName, cookieValues);
        return this;
    }

    @Override
    public WebTestClient.Builder defaultCookies(
            Consumer<MultiValueMap<String, String>> cookiesConsumer) {
        this.webClientBuilder.defaultCookies(cookiesConsumer);
        return this;
    }

    @Override
    public WebTestClient.Builder filter(ExchangeFilterFunction filter) {
        this.webClientBuilder.filter(filter);
        return this;
    }

    @Override
    public WebTestClient.Builder filters(Consumer<List<ExchangeFilterFunction>> filtersConsumer) {
        this.webClientBuilder.filters(filtersConsumer);
        return this;
    }

    @Override
    public WebTestClient.Builder exchangeStrategies(ExchangeStrategies strategies) {
        this.webClientBuilder.exchangeStrategies(strategies);
        return this;
    }

    @Override
    public WebTestClient.Builder responseTimeout(Duration timeout) {
        this.responseTimeout = timeout;
        return this;
    }

    @Override
    public WebTestClient.Builder apply(WebTestClientConfigurer configurer) {
        configurer.afterConfigurerAdded(this, this.httpHandlerBuilder, this.connector);
        return this;
    }


    @Override
    public WebTestClient build() {
        ClientHttpConnector connectorToUse = this.connector;
        if (connectorToUse == null) {
            Assert.state(this.httpHandlerBuilder != null, "No WebHttpHandlerBuilder available");
            connectorToUse = new HttpHandlerConnector(this.httpHandlerBuilder.build());
        }

        return new DefaultWebTestClient(this.webClientBuilder,
                connectorToUse, this.responseTimeout, new DefaultWebTestClientBuilder(this));
    }

}
